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Spinel oxide materials have been widely used as oxygen evolution catalysts to enhance the photoelectrochemical (PEC) performance of photoelectrodes. Herein, we demonstrate that the water splitting efficiency of a photoanode can be further enhanced by introducing its photothermal effect. Under near-infrared radiation, the temperature of the NiCo2O4/BiVO4 photoanode increases moderately, leading to improved water oxidation kinetics and charge transport simultaneously. With the assistance of the photothermal effect, the obtained photoanode reaches a photocurrent density of 6.20 mA cm-2 at 1.23 V vs reversible hydrogen electrode. A series of spinel-type MCo2O4 oxides (M = Mn, Zn, Cu, and Fe) are deposited on the surface of the BiVO4 photoanode to show similar photothermally enhanced PEC performance. The research discovery provides a way for improving the catalytic activity of photoanode materials with a photothermal effect, which may be applied to various fields of energy conversion, including CO2 reduction, N2 fixation, and pollutant degradation.

It is possible to improve the machinability of aluminum nitride-hexagonal boron nitride (AlN-h-BN) ceramics while maintaining high strength and high thermal conductivity. The composite ceramics with 0–30 wt% BN as secondary phase were prepared by hot pressed sintering, using yttrium oxide (Y2O3) as sintering aid. The phase composition, density, microstructure, mechanical properties, thermal conductivity, and dielectric properties were investigated. The sintering additives were favorable to purify the grain boundaries and improve densification, reacting with oxide impurities on the surface of raw material powder particles. The optimum BN content improved the flexural strength and fracture toughness of composite ceramics with 475 MPa and 4.86 MPa·m1/2, respectively. With increasing the amount of BN, the thermal conductivity and hardness of composites gradually decreased, but the minimum value of thermal conductivity was still 85.6 W·m−1·K−1. The relative dielectric constant and dielectric loss tangent of the samples ranged from 6.8 to 8.3 and from 2.4 × 10−3 to 6.4 × 10−3, respectively, in 22–26 GHz.

Increasing the availability of π-electron in graphitic carbon nitride (g-C3N4) can reduce the band gap and thus enhance the photocatalytic hydrogen (H2) generation activity upon exposure to visible light. However, such strategy has not yet been largely applied to increase the H2 generation of g-C3N4. Herein, we successfully increased the amount of π-electron in g-C3N4 by incorporating π-electron-rich benzene rings through copolymerization of melamine and trimesic acid in air. The incorporation of benzene rings not only extends the light absorption of g-C3N4 to 650 nm, but also improves the electrical conductivity due to delocalization of π electrons in benzene rings. As a result, a 3.4 times enhancement of photocatalytic H2 generation was achieved from the g-C3N4 with benzene ring incorporation in comparing with that of pristine g-C3N4. More interestingly, H2 generation still occurs under irradiation of the light of λ ≥ 490 nm, above the absorption edge of pristine g-C3N4 (∼ 460 nm), illustrating the positive effectiveness of incorporated benzene rings on enhancing the H2 generation capacity of g-C3N4. The present work manifests the advantages of increasing π-conjugated electrons on designing highly active g-C3N4 photocatalysts.

Sub-5 nm monodispersed metal oxides have been attracting much attention in energy storage due to their large electrolyte ion-accessible surface areas and high specific capacities. However, the high surface free energy of ultrasmall nanoparticles inevitably results in their serious aggregation, leading to degraded electrochemical activities and poor cycling stability. Herein, a two-stage microimpinging stream reactor (TS-MISR) strategy that combines a first homogeneous premixing stage with a subsequent microimpinging stream reacting stage has been constructed for the controllable synthesis of Ni–Co–O/RGO composites (NCG). Benefiting from the enhanced micromixing efficiency and better process control of TS-MISR, monodispersed ultrasmall Ni–Co–O particles (3–4 nm) are evenly grown on the RGO flakes to generate a large specific surface area (293.2 m2 g−1), quantities of desirable mesopores (2–4 nm), as well as a strong synergistic effect between Ni–Co–O particles and conductive RGO flakes, hence providing more superficial electroactive sites, fast electron transfer and short diffusion paths for electrolyte ions to participate in faradaic redox reactions. The as-prepared NCG-MM exhibits a large specific capacity of 912.4 C g−1 (capacitance of 2281 F g−1) at the current density of 1 A g−1, good rate capability and cycling stability. Coupled with the activated carbon (AC) negative electrode, the assembled pouch-type NCG//AC asymmetric supercapacitor displays a prominent areal energy density (0.898 mW h cm−2 at 0.8 mW cm−2) and an excellent cycling stability (∼90.5% capacity retention after 8000 cycles). In addition, this strategy opens up an important prospect for the controllable synthesis of monodispersed metal oxide/graphene composites for application in batteries, sensors and catalysis.

BACKGROUND: Methyl levulinate (ML) is a promising green candidate for bio‐based diesel fuels and fuel additives. An effective method for synthesizing ML from levulinic acid (LA) catalyzed by cheap metal salt catalyst under mild conditions was developed. A series of metal salts were screened for the synthesis of ML from LA, and aluminum chloride was identified as a suitable catalyst for this process. RESULTS: The effects of catalyst loading, the molar ratio of methanol to LA, reaction temperature and reaction time on LA conversion and ML yield were investigated. The response surface method was used to optimize the process, and the model validation experiment showed that the predicted values corresponded well with the actual ones. Under the optimum conditions of reaction temperature 343 K, reaction time 1.5 h, aluminum chloride 1.14 g and molar ratio of methanol to LA 8:1, a high ML yield of 95.0 mol% could be obtained. Moreover, a kinetic model was proposed to evaluate the reaction process at a temperature range of 30–70 °C. The first‐order pseudo model was considered most suitable (R² > 0.99), and the activation energy of the reaction Eₐ was estimated to be 32.28 kJ mol⁻¹. Investigation of the reuse of the catalyst revealed that it retained good catalytic activity after repeated use for ten times. CONCLUSION: A green and efficient process of ML production from LA catalyzed by the metal salt aluminum chloride was developed. © 2020 Society of Chemical Industry

Glycerol levulinate ketal (GLK) is a novel biobased chemical compound with great potential for industrial applications, especially in the areas of green solvents and polymeric materials. For the fi...

Crystalline metal-organic frameworks of divalent transition metal terephthalate belong to a new kind of high-capacity lithium storage materials. In this paper, CoCl 2 aqueous solution and CoCl 2 ·6H 2 O particles are comparatively used as starting materials to react with aqueous lithium terephthalate (Li 2 TP), resulting in the hierarchical architectures of dihydrate cobalt terephthalate (CoTP·2H 2 O No.1, No.2) by a solution-based π-π stacking self-assembly, respectively. Each of the two hydrated samples, as well as its well-crystallized anhydrous counterpart (CoTP No.1 or No.2), acquire a specific surface area no bigger than 4.5 m 2 g −1 but deliver a reversible capacity no less than 815.0 mAh g −1 at 200 mA g −1 in the 100th cycle. The decreasing order of lithium-storage capability (CoTP·2H 2 O No.1 2 O No.2 −1 , the 350th cycle) of CoTP No.2 structure and indicates a successful approach to the facile preparation of the organic anode material for high-performance lithium-ion batteries.

The ability to rationally design binder-free electrode materials that possess interconnected nanostructures is highly desirable for lithium-ion batteries (LIBs) with long cycling and excellent rate performances. Such electrode containing pores between nanostructures imparts large-area contact with electrolyte, improved electrical conductivity with current collector, and good structural stability and mechanical integrity. Herein, we report, for the first time, outstanding cycling stability and rate performance of CuO electrode in LIBs. CuO nano-labyrinths (NLs) composed of densely interlaced nanowalls on Cu foil are crafted via a facile solution-based etching process. It is notable that macroscopic and mesoscopic pores are found to ubiquitously present among the adjacent CuO nanowalls and within the nanowall, respectively (i.e., forming hierarchically porous CuO NLs). Intriguingly, CuO NLs anodes yield an ultralong cycling stability, that is, a specific capacity of 320 mA h g−1 after 800 cycles without the capacity fading at high current density of 1 A g−1, and an outstanding high-rate performance (up to 30 C). This is a direct consequence of unique synergistic effects of hierarchical pores and interlaced nanostructures. Moreover, a further enhancement of reversible capacity is achieved by deposition Si thin film on the surface of CuO NLs. Such interlaced nanowall-containing structures with hierarchical pores represent an important type of architectures that underpin the development of electrode materials for long cycle-life energy storage devices.

Though solar cells are one of the promising technologies to address the energy crisis, this technology is still far from commercialization. Thermoelectric materials offer a novel opportunity to convert energy between thermal and electrical aspects, which show the feasibility to improve the performance of solar cells via heat management and light harvesting. Polymer–inorganic thermoelectric nanocomposites consisting of inorganic nanomaterials and functional organic polymers represent one kind of advanced hybrid nanomaterials with tunable optical and electrical characteristics and fascinating interfacial and surface chemistry. During the past decades, they have attracted extensive research interest due to their diverse composition, easy synthesis, and large surface area. Such advanced nanomaterials not only inherit low thermal conductivity from polymers and high Seebeck coefficient, and high electrical conductivity from inorganic materials, but also benefit from the additional interface between each component. In this review, we provide an overview of interfacial chemistry engineering and electrical feature of various polymer–inorganic thermoelectric hybrid nanomaterials, including synthetic methods, properties, and applications in thermoelectric devices. In addition, the prospect and challenges of polymer–inorganic nanocomposites are discussed in the field of thermoelectric energy.

Summary Oxidation of formate to CO2 is catalyzed via the donation of electrons from formate dehydrogenase (FDH) to nicotinamide adenine dinucleotide (NAD+), and thus the charge transport characteristics of FDH become essential but remain unexplored. Here, we investigated the charge transport through single-enzyme junctions of FDH using the scanning tunneling microscope break junction technique (STM-BJ). We found that the coupling of NAD+ with FDH boosts the charge transport by ∼2,100%, and the single-enzyme conductance highly correlates with the enzyme activity. The combined flicker noise analysis demonstrated the switching of the coenzyme-mediated charge transport pathway and supported by the significantly reduced HOMO-LUMO gap from calculations. Site-specific mutagenesis analysis demonstrated that FDH-NAD+ stably combined own higher bioactivity and boosts charge transport, and the coupling has been optimized via the natural selection. Our work provides evidence of hydrogen bond coupling in bioactivity but also bridges the charge transport through single-enzyme junctions and enzyme activities., Graphical Abstract, Highlights • Binding of NAD+ with FDH boosts the charge transport by more than 2,100% • Single-enzyme conductance highly correlates with the enzyme activity • Hydrogen bond bridges the charge transport and enzyme activities • Experiments combined with calculations probe switching of charge transport pathway, Analytical Chemistry; Biotechnology; Molecular Biology

Hierarchical TiO2-based hollow spheres were successfully synthesized via a hydrothermal method using FeSO4·7H2O, CoSO4·7H2O and ZnSO4·7H2O as soft templates. The as-prepared hollow spheres are well dispersed with the diameters of 2–4 μm. The shell and the interior surface of the spheres are composed of loosely packed grains, which provide a large specific surface area to facilitate lithium-ion diffusion processes. Among the three types of hybrid hollow spheres, TiO2/Fe2O3 shows the highest reversible capacity and best cycling stability (discharge capacities of 290.8 and 210.5 mAh/g were achieved after 100 cycles at 0.1C and 1C, respectively) and rate performance (from 461.1 mAh/g at 0.1C to 79.3 mAh/g at 5C with recovery to 288.6 mAh/g at 0.1C) for anode materials in lithium-ion batteries.

Summary Transition metal oxide catalysts with high oxygen reduction activity and durability are highly desirable for use in fuel cells and metal-air batteries. Herein we report, for the first time, the oxygen reduction activity of hollow porous spinel AB 2 O 4 microspheres, where A = Zn 2+ and B = Mn 3+ and/or Co 3+ (i.e., ZnMn x Co 2−x O 4 ). Among them, ZnMnCoO 4 ( x = 1) microspheres exhibit the best oxygen reduction activity with a half-wave-potential only 50 mV lower than that of the Pt/C counterpart and an excellent durability in the alkaline solution. Importantly, the electronic transition of Co 3+ ions from low-spin state in commercial Co 3 O 4 catalyst to a mixed high-spin and low-spin state in ZnMnCoO 4 catalyst was found to weaken the Co 3+ -OH bond and facilitate the O 2− /OH − displacement. The density functional theory calculation substantiated that ZnMnCoO 4 displayed a more favorable binding energy with O 2 and oxygenated species, thereby enabling the fast reaction kinetics in the oxygen reduction reaction process.

The effects of preferential flow on plant root and soil have not been deeply studied. Research on the combination of wetland vegetation, hydrology, and soil can provide a theoretical basis for wetland vegetation restoration and soil salinization control. We integrated preferential flow, root, and soil to study the distribution characteristics of the root architecture and soil nutrient of two different ecotypes of Phragmites communis (P. communis) in the Yellow River Delta on a small scale. We found that both root architectures included root length, width, surface area, volume, and biomass and soil nutrients included soil organic carbon, organic matter and total nitrogen decreased with the increase of soil depth. Large P. communis (LP) not only had significantly larger root length, width, surface area, but also had significantly higher soil organic carbon, organic matter, total nitrogen, and available phosphorus than small P. communis (SP). The root architectures of SP in the preferential flow area (PFA) were significantly greater than those in the matrix flow area (MFA). The contents of soil organic carbon, organic matter, and total nitrogen in LP grown in the PFA were obviously higher than those in the MFA. Based on correlation analysis, root architectures had remarkably positive correlations with soil organic carbon, organic matter, and total nitrogen. These findings suggest that preferential flow improves the root-soil system. By artificially adding peat and biochar and changing irrigation methods, the possibility of preferential flow can be increased, plant root growth and soil nutrient can be improved, so as to resist the damage of soil salinization. In addition, different ecotypes of P. communis should be planted to improve soil salinization. LP and SP are suitable for slight and heavy soil salinization areas respectively.

Co-axial silicon-coated carbon nanotubes (CNTs/Si) were successfully synthesized via a hydrothermal method. Sandwich-like carbon-coated CNTs/Si were obtained by an additional carbon coating. The as-prepared materials show superior cycling performance as anode materials in lithium ion batteries with a current density as high as 500 mA g−1 with no observable structural changes during the charge/discharge process. In addition, stable reversible discharge capacities as high as 1508.5 mA h g−1 after 1000 cycles were obtained. At higher current densities of 1 A g−1 and 2 A g−1, the CNTs/Si/C nanotubes also showed ideal cycling performance with reversible discharge capacities of 1216.6 mA h g−1 and 932.2 mA h g−1, respectively. The sandwich-like hollow tube structure of CNTs/Si/C not only alleviates the volume change during cycling, but also facilitates Li-ion and electron transport, and stabilizes the SEI layer. These results suggest that sandwich-like CNTs/Si/C nanotubes are a promising anode material for lithium ion batteries.

Hollow SnO2 spheres with oriented cone-like SnO2 nanoparticle shells were synthesized by a one-step hydrothermal process using NaF as the morphology controlling agent. The resulting hollow SnO2 sphere electrode exhibits high reversible capacity (initial charge and discharge capacities of 1342.9 and 1947.6 mAh/g at 0.1 C and 1235.4 and 1741.3 mAh/g at 1 C) and good cycling stability (discharge capacities maintained 758.1 and 449.6 mAh/g after 100 cycles at 0.1 C and 1 C, respectively). Good rate performance was also obtained (1234.5 mAh/g at 0.1 C, 884.2 mAh/g at 0.2 C, 692.4 mAh/g at 0.5 C, 497.6 mAh/g at 1 C, 315.8 mAh/g at 2 C and 80.6 mAh/g at 5 C, and more importantly, when the current density returns to 0.1 C, a capacity of 869.6 mAh/g can be recovered. The observed electrochemical performance can attributed to the hollow structure, the use of NaF for morphology control and the unique oriented cone-like shell of the particles.

In this paper, a framework of macro-/micro-porous carbon derived from commercial lignin is prepared by one-step carbonization/activation method and then utilized as sulfur-loading matrix to assay the effect of sulfur-loading time on the structural and electrochemical properties of carbon-sulfur composite (C-S-t, t defined as sulfur-loading time). As-prepared porous carbon possesses a high specific surface area of 1211.6 m 2 g −1 and a pore volume of 0.59 cm 3 g −1 , acquires oxygen-containing functional groups on the surface of framework and functionalizes for the chemical adsorption of elemental sulfur. Under N 2 atmosphere (flow rate ∼ 60 mL min −1 ) the longer is the sulfur-loading time, the lower value is the total sulfur content of carbon-sulfur composite and the higher percentage of sulfur embedded within the micropores. At a sulfur-loading time of ∼10 h, the resulting C-S-10 composites have a total sulfur content as low as 50.0 wt% (44.8% in micropores) but exhibit the better electrochemical performances than C-S-6 composites formed at 6 h (sulfur ∼ 58.8 wt%, 29.4% in micropores). Therefore, aside from the structural properties of porous carbon, an optimized sulfur-loading time, as well as the chemical binding between carbon host and sulfur, should be considered to develop high-performance cathode materials for liquid electrolyte lithium-sulfur (Li-S) batteries.

Sodium manganese hexacyanoferrate (PBM) is one of the most promising cathode materials for sodium-ion batteries due to its high theoretical capacity, high voltage, and low cost. However, its cycling performance is limited by serious Mn ions dissolution during Na+ insertion/extraction. In this work, a facile in situ ion-exchange strategy is developed to synthesize sodium manganese hexacyanoferrate coated by sodium nickel hexacyanoferrate (PBM@PBN). The as-prepared PBM@PBN showed superior cyclic stability and enhanced rate capability. PBM@PBN exhibited a high reversible capacity of 126.9 mAh g−1 (1 C), with a capacity retention of 74.3% after 800 cycles. ICP results proved that superior cyclic stability was attributed to the inhibition of Mn ions dissolution by PBN coating. Besides, PBM@PBN also exhibited enhanced rate capability, and it delivered a high capacity of 87.2 mAh g−1 at 10 C. Ex-situ XRD proved that the PBM@PBN undergoes a reversible structural change (monoclinic ↔ cubic/tetragonal) during the whole cycle. PBN coating inhibited the PBM from suffering serious Mn ions dissolution during Na+ insertion/extraction, thus ensured the framework stability of PBM during long-term cycling and contributed to the excellent electrochemical performance. The simple preparation of PBM@PBN makes it accessible for large-scale applications.

The ability of photoanodes to simultaneously tailor light absorption, charge separation, and water oxidation processes represents an important endeavor toward highly efficient photoelectrochemical (PEC) water splitting. Here, a robust strategy is reported to render markedly improved PEC water splitting via sandwiching a photothermal Co3 O4 layer between a BiVO4 photoanode film and an FeOOH/NiOOH electrocatalyst sheet. The deposited Co3 O4 layer manifests compelling photothermal effect upon near-infrared irradiation and raises the temperature of the photoanodes in situ, leading to extended light absorption, enhanced charge transfer, and accelerated water oxidation kinetics simultaneously. The judiciously designed NiOOH/FeOOH/Co3 O4 /BiVO4 photoanode renders a superior photocurrent density of 6.34 mA cm-2 at 1.23 V versus a reversible reference electrode (VRHE ) with outstanding applied bias photon-to-current efficiency of 2.72% at 0.6 VRHE . In addition to the metal oxide, a wide variety of metal sulfides, nitrides, and phosphides (e.g., CoS, CoN, and CoP) can be exploited as the heaters to yield high-performance BiVO4 -based photoanodes. Apart from BiVO4 , other metal oxides (e.g., Fe2 O3 and TiO2 ) can also be covered by photothermal materials to impart significantly promoted water splitting. This simple yet general strategy provides a unique platform to capitalize on their photothermal characteristics to engineer high-performing energy conversion and storage materials and devices. National Research Foundation (NRF) This work was supported by the National Natural Science Foundation of China (51902297, 52002361, and 51903080), the Fundamental Research Funds for National Universities, China University of Geosciences (Wuhan), the Fund of the Key Laboratory of Catalysis and Energy Materials Chemistry of Ministry of Education & Hubei Key Laboratory of Catalysis and Materials Science, and the Singapore National Research Foundation Investigatorship (NRF-NRFI2018-03).

Well-controlled nanostructures and a high fraction of Sn/Li2O interface are critical to enhance the coulombic efficiency and cyclic performance of SnO2-based electrodes for lithium-ion batteries (LIBs). Polydopamine (PDA)-coated SnO2 nanocrystals, composed of hundreds of PDA-coated “corn-like” SnO2 nanoparticles (diameter ca. 5 nm) decorated along a “cob”, addressed the irreversibility issue of SnO2-based electrodes. The PDA-coated SnO2 were crafted by capitalizing on rationally designed bottlebrush-like hydroxypropyl cellulose-graft-poly (acrylic acid) (HPC-g-PAA) as a template and was coated with PDA to construct a passivating solid-electrolyte interphase (SEI) layer. In combination, the corn-like nanostructure and the protective PDA coating contributed to a PDA-coated SnO2 electrode with excellent rate capability, superior long-term stability over 300 cycles, and high Sn→SnO2 reversibility.

Interconnected nickel bicarbonate (Ni(HCO3)2) hollow spheres were produced and exploited for the first time as an anode of lithium ion batteries, delivering the 80th reversible capacity of 1442 mAh g–1 at a current rate of 100 mA g–1, which is 3.9 times the theoretical capacity of commercial anode graphite. The time-dependent study suggested a self-sacrificial templating formation mechanism that yielded intriguing interconnected hollow structures. X-ray photoelectron spectroscopy measurements on cycled electrodes indicated that both the deep oxidation of Ni2+ into Ni3+ and the reversible reactions in HCO3– accounted for the ultrahigh capacity of Ni(HCO3)2 in comparison to its generally accepted theoretical capacity of 297 mAh g–1. Morphological characterizations revealed that the interconnected hollow structures enabled the enhanced rate performance and cycling stability, compared to those of the solid counterpart, because of their larger contact areas with electrolyte and better buffering effect to accom...

As a lithium-ion battery (LIB) anode, transition metal oxide nanostructures usually exhibit an initially decreasing and subsequently increasing trend of specific discharge capacity, owing to the gradually enhanced interfacial storage capability. In this paper, a novel base-catalyzed reaction of nickel acetate is used to synthesize flowerlike hollow architectures of basic carbonate based precursor and then to obtain NiO flowerlike porous hollow nanostructures with a high surface-to-volume ratio. As a LIB anode at 200 mA g −1 , the observed discharge capacity of the working electrode decreases from an initial value of 1584.7 mAh g −1 to the minimum value of 867.5 mAh g −1 in the 76th cycle and then increases to the maximum value of 2142.8 mAh g −1 in the 350th cycle. In each cycle, an interfacial fraction of the discharge capacity can be clearly distinguished and quantitatively estimated according to the discharging behaviors. These prove that the seemingly battery-to-pseudocapacitor transition relates both to bulk capacity loss and to interfacial capacity gain, depending upon the applied C-rate. Furthermore, the ordered arrangement of gradually crystallized Li 2 CO 3 , a main component of solid-electrolyte interface (SEI) layer, and its non-faradaic (double-layer capacitive) and faradaic (further reverse lithiation-delithiation) contributions may explain the over-compensating ability of interfacial storage.

Nickel-cobalt borides (denoted as NCBs) have been considered as a promising candidate for aqueous supercapacitors due to their high capacitive performances. However, most reported NCBs are amorphous that results in slow electron transfer and even structure collapse during cycling. In this work, a nanocrystallized NCBs-based supercapacitor is successfully designed via a facile and practical microimpinging stream reactor (MISR) technique, composed of a nanocrystallized NCB core to facilitate the charge transfer, and a tightly contacted Ni-Co borates/metaborates (NCBi ) shell which is helpful for OH- adsorption. These merits endow NCB@NCBi a large specific capacity of 966 C g-1 (capacitance of 2415 F g-1 ) at 1 A g-1 and good rate capability (633.2 C g-1 at 30 A g-1 ), as well as a very high energy density of 74.3 Wh kg-1 in an asymmetric supercapacitor device. More interestingly, it is found that a gradual in situ conversion of core NCBs to nanocrystallized Ni-Co (oxy)-hydroxides inwardly takes place during the cycles, which continuously offers large specific capacity due to more electron transfer in the redox reaction processes. Meanwhile, the electron deficient state of boron in metal-borates shells can make it easier to accept electrons and thus promote ionic conduction.

Commercial lithium-ion batteries (LIBs), limited by their insufficient reversible capacity, short cyclability, and high cost, are facing ever-growing requirements for further increases in power capability, energy density, lifespan, and flexibility. The presence of insulating and electrochemically inactive binders in commercial LIB electrodes causes uneven active material distribution and poor contact of these materials with substrates, reducing battery performance. Thus, nanostructured electrodes with binder-free designs are developed and have numerous advantages including large surface area, robust adhesion to substrates, high areal/specific capacity, fast electron/ion transfer, and free space for alleviating volume expansion, leading to superior battery performance. Herein, recent progress on different kinds of supporting matrixes including metals, carbonaceous materials, and polymers as well as other substrates for binder-free nanostructured electrodes in LIBs are summarized systematically. Furthermore, the potential applications of these binder-free nanostructured electrodes in practical full-cell-configuration LIBs, in particular fully flexible/stretchable LIBs, are outlined in detail. Finally, the future opportunities and challenges for such full-cell LIBs based on binder-free nanostructured electrodes are discussed.

A series of metal-modified phosphotungstates were prepared and performed for direct synthesis of ethyl levulinate from fructose in ethanol. Considering the cost of catalysts, catalytic activity of catalysts, and easy separation of catalysts together, K-HPW-1 was chosen as the most suitable catalyst for synthesis of ethyl levulinate from fructose. A high ethyl levulinate yield of 64.6 mol% was obtained at 150 °C within 2 h in ethanol. The introduction of low polar toluene as a co-solvent improved the yield of ethyl levulinate to 68.7 mol%. The recovered catalyst remained high activity with the yield of ethyl levulinate converted from fructose above 50 mol% after being used five times. Moreover, the generality of the catalyst was further demonstrated by glucose, sucrose, inulin, and cellulose with ethyl levulinate yielding 14.5, 35.4, 52.3, and 14.8 mol%, respectively.

Synthesis of materials with desirable nanostructures is a hot research topic owing to their enhanced performances in contrast to the bulk counterparts. Herein, dumbbell-shaped cobalt carbonate (CoCO 3 ) nano architectures and the bulk counterpart of CoCO 3 rhombohedra are prepared via a facile hydrothermal route in the presence and absence of ascorbic acid (AA), respectively. By comparison, it has been found that: the addition of AA in the hydrothermal crystallization system changes the shape of the building blocks from Co 2 CO 3 (OH) 2 nanosheets to CoCO 3 nanoparticles, and then further influences the final configuration of the products. When applied as anodes of lithium ion batteries, CoCO 3 dumbbells deliver a 100th capacity of 1042 mAh g −1 at 200 mA g −1 and even exhibit a long-term value of 824 mAh g −1 over 500 cycles at 1000 mA g −1 , which are much higher than the rhombohedral counterparts with corresponding 540 and 481 mAh g −1 respectively. The much higher capacity, better cycling stability and enhanced rate performance of CoCO 3 dumbbells can be attributed to the higher specific surface area, smaller charge transport resistance and better structure stability resulting from the slight doping (∼4.6 wt%) of AA, and also relate with a novel lithium storage mechanism in CoCO 3 .

Graphene oxide (GO) possesses high electron conductivity and good chemical-binding ability and thus can be used as a multifunctional additive for the preparation and application of electrode materials. As for the hydrothermal crystallization of MnCO3 herein, the absence of GO causes the formation of MnCO3 flower-like architectures composed of secondary spindles, while the presence of GO induces the flower-to-petal structural conversion and results in MnCO3 spindle–GO composites. When applied as Li-ion battery anodes, the composite electrode delivers an initial coulombic efficiency (CE) of 71% and a reversible capacity of 1474 mA h g−1 in the 400th cycle, much higher than those of MnCO3 flowers (the initial CE ∼ 58%, the 400th capacity ∼ 1095 mA h g−1) operated under the same conditions. In particular, the combination of discharging behavior and its differential capacity profile has been successfully used to estimate the interfacial contribution fraction (42%) of the whole reversible capacity (i.e., 1474 mA h g−1) enhanced by the in situ mixing of 8.3 wt% GO.

Multicomponent composites with an integrated lattice structure can possess an atomic-scale distribution of different components within the crystallites and may express an enhanced synergistic effect compared to the mechanical mixture. In this paper, a series of cobaltous-ferrous carbonates CoxFe1−xCO3 (x = 0, 0.2, 0.4, 0.6, 0.8 and 1) have been synthesized via a facile hydrothermal route with the assistance of ascorbic acid (AA). The four multicomponent CoxFe1−xCO3 composites exhibit hexagonal structures similar to those of the monocomponents FeCO3 and CoCO3, and the resulting rodlike crystallites give aspect ratios and unit-cell parameters linearly changed along with the increasing x value, indicating the successful synthesis of CoxFe1−xCO3 composites at an arbitrary Co/Fe molar ratio. When used as lithium ion battery anodes, the CoxFe1−xCO3 composites can well inherit both the high-conductivity characteristic of CoCO3 and the low-rate cycling stability of FeCO3. In particular, each composite presents better electrochemical properties than the corresponding xCoCO3 + (1 − x)FeCO3 mixture, mainly assigned to an inner atomic-scale synergistic effect within the formula CoxFe1−xCO3. Therefore, CoxFe1−xCO3 composites may serve as novel high-capacity LIB anode materials for practical application, and also a facile strategic approach is introduced for the full-molar-ratio synthesis of multicomponent composites.

The physicochemical properties of coix seed oil (CSO) liposomes prepared by five different methods were evaluated for morphology, encapsulating efficiency, particle size, storage stability, and in vitro release. The different preparation methods resulted in several types of vesicles with different properties. The type of vesicles was closely related to leakage pattern, which affected the storage stability and in vitro release profiles. Ethanol injection method was the best choice for preparing safe and stable liposomes with controlled release. The release mechanisms might account for the diffusion of CSO, and Higuchi was the most suitable model for liposomes stored at high temperature or released in simulated intestinal fluid (SIF).

Porous AMn2O4 (A = Zn, Zn0.5Co0.5, Co) microspheres have been prepared through a carbonate co-precipitation and subsequent heat treatment at 600 °C. X-ray diffraction (XRD) patterns and scanning electron microscope (SEM) images reveal that, the porous AMn2O4 microspheres with hausmannite (Mn3O4) structure are composed of well-defined primary nanoparticles, and these nanoparticles have the size of 30–100 nm. As lithium-ion battery anodes, the electrochemical properties of porous AMn2O4 microspheres are determined by their chemical compositions. The porous ZnMn2O4 microspheres can retain a discharge capacity of 698.8 mAh g− 1 after 50 charge–discharge cycles, which is much better than the other two oxides. The CoMn2O4 shows the highest discharge potential among three samples. Interestingly, the Zn0.5Co0.5Mn2O4 inherits the shortage of CoMn2O4 and ZnMn2O4, and its cycling stability is the worst.

Crystallization and oriented attachment of monohydrocalcite (MHC) for the self-organization of dumbbell-like superstructures in the absence of any additives, as well as the crystalline phase transformation of MHC to anhydrous calcium carbonate (CaCO3), have been systematically described in this paper. In Mg2+-containing artificial seawater at 4 °C, the dissolution of initially formed amorphous calcium carbonate (abbreviated as ACC) cannot be detected prior to the crystallization of MHC, and the detected inter-particle hydrogen bonds probably induce the oriented attachment of nanocrystalline MHC building blocks with a protective Mg-rich layer. As for the crystalline phase transformation of MHC to an anhydrous CaCO3 (i.e., vaterite, aragonite or calcite), two novel aspects have been highlighted: (i) the unexpected detection of unstable vaterite for the calcination of solid-state MHC, (ii) the unique product of cube-shaped or dumbbell-like superstructures of tiny calcite rhombohedrons from Mg2+-free artificial seawater at 30 °C. In particular, the effect of Mg2+-chelators (organic acetylacetone or inorganic sodium hydroxide) on the abnormal solution-mediated transformation of MHC to calcite may be potentially applied for biomimetic synthesis purposes.

Summary In this research, microcapsules containing Chinese yak butter (MYB) were prepared by spray drying technique using rice syrup/whey protein isolate/sodium caseinate as wall materials. The physiochemical properties, nutritional value, stability and in vitro digestion behaviour of MYB were analysed. The results indicated that MYB were round-shaped particles with good flow properties, high microencapsulation efficiency (97.4%) and prolonged shelf life. After rehydration, the reconstituted emulsion was found to be uniform and stable. Results also suggested yak butter (YB) with more kinds of fatty acids and a ω-3/ω-6 ratio higher than 0.33 was more nutritional for human consumption than commercial milk powder, and spray drying process had nearly no side effects on nutritional value of YB. In addition, the comparative analysis of leakage behaviour after exposure to different simulated gastrointestinal tract fluids indicated that YB could be efficiently leaked out of MYB except a ratio bound to wall materials.

The preparation of porous Mn2O3 boxes has been developed via a carbonate precursor route. As a Li-ion battery anode, it delivers a high reversible capacity of 1442 mA h g(-1) over 600 cycles at 800 mA g(-1), and 65% of the capacity originates from the gradually emerging interfacial storage contribution.

A series of supported phosphotungstic acid (H3PW12O40, HPW) catalysts, including HPW/β, HPW/Sn-β, HPW/H-Y, HPW/H-ZSM-5, HPW/USY, HPW/ReUSY, and HPW/SBA-15, were prepared using an impregnation method for alcoholysis of fructose to ethyl levulinate in ethanol. Among these catalysts, HPW/H-ZSM-5 showed the highest catalytic activity, and the yield of ethyl levulinate from fructose increased with increasing phosphotungstic acid loading. The yield of ethyl levulinate reached 43.1% at 160 °C for 2 h over 20 wt.% HPW/H-ZSM-5, and the solid catalyst could be reused at least three times. EL yields of 19.1%, 27.3%, 37.4%, and 8.7% could be obtained from glucose, sucrose, inulin, and cellulose, respectively. Furthermore, the catalysts were characterized by BET surface area, X-ray diffraction, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. HPW/H-ZSM-5 showed good catalytic activity for the direct production of ethyl levulinate from fructose.

Akebia trifoliata var. australis seed oil (ASO) was used as an edible oil in China. However, in-depth research studies on ASO have yet to be conducted for production of plastic fats in food industry. In this work, an immobilized lipase from Thermomyces lanuginosus (TL IM) was employed to catalyze palm stearin (PS) with different ratios of ASO in a laboratory-scale operation at 60 °C. The physical properties [e.g., fatty acid profile, slip melting point (SMP), solid fat content (SFC), polymorphic form, and microstructure] of physical blends (PBs) were analyzed and compared with those of the interesterified products (IPs). Results showed that SMPs of IPs (33.20-37.60 °C) decreased compared with those of PBs (48.03-49.30 °C). Meanwhile, IPs showed a good SFC range from 16.11% to 28.29% at 25 °C with mostly β' polymorphic forms determined by X-ray diffraction analysis. It should be mentioned that no trans fatty acids (TFAs) were detected in any products, suggesting much more health-benefits of IPs. Texture tests showed that PBs (3318.19 ± 86.67 g) were markedly harder than IPs (557.02 ± 12.75 g). Conclusively, our study demonstrated that ASO can be utilized to produce trans-free plastic fats with good qualities through lipase-catalyzed interesterification.

Metal oxide or hydroxide nanomaterials were synthesized by an arc-discharge method in an aqueous electrolyte, with different metal electrodes. The morphologies of the obtained nanomaterials were controlled successfully. From the results of XRD and TEM, it is obvious that different products had different morphologies under the same NaCl electrolyte.

On the reliability evaluation, the phenomenon of surface roughness on the Al surface of DBA (Direct Brazed Aluminum) on power device is confirmed. This surface roughness is generated by cyclic thermal stress under thermal cycle test. In this study, the surface roughness characteristic after thermal cycle test is executed to DBA substrate and the generating mechanism was investigated. Furthermore, the effect on the fatigue life of solder joint on DBA substrate is also investigated.Copyright © 2011 by ASME

Submicron-sized orthorhombic LiMnO2 (O-LiMnO2) crystals with clear edges can be successfully prepared by a hydrothermal route using LiOH and porous Mn2O3 as precursors at 180°C for 16 h. As a reducing agent, hydrazine hydrate (N2H4·H2O) was introduced into the hydrothermal reaction systems of dark-green O-LiMnO2 at a N2H4·H2O:Mn2O3 molar ratio of 10.6:100, inhibiting the common impurity formation of red Li2MnO3 therein. At room temperature, the relatively purified O-LiMnO2 gives a high reversible capacity and good cyclability, showing a maximum discharge capacity of 216 mAh g−1 and a retention value of 200 mAh g−1 over 30 cycles at 0.1 C between 2.0 and 4.3 V, whereas the unpurified O-LiMnO2 showed a maximum discharge capacity of 200 mAh g−1, and fast decayed to 165 mAh g−1 during the 30th cycle. Moreover, cyclic voltammetry measurements and X-ray diffraction patterns of the cycled electrode materials prove the irreversible phase transformation of O-LiMnO2 to spinel LiMn2O4 upon cycling, suggesting that the easily Mn(IV)-doped synthesis of O-LiMnO2 hinder its potential application as lithium-ion battery cathodes.